There are many high frequency electrical signal modulation techniques used in the field of home automation and energy metering, such as amplitude modulation (AM), spread frequency shift keying (SFSK), and frequency shift keying (FSK). Information may be encoded according to different protocols which determine the format of the messages to be sent, where each message includes binary signals which control the modulator at the sending end. Upon reception, the demodulator detects the high frequency modulated signals and extracts the binary information of the message sent. The extracted binary signals are then interpreted by an appropriate device, such as a microprocessor, depending on the protocol.
Because the appliances of a home automation system may receive and send messages, they are generally equipped with a modulation/demodulation device. Yet, appliances of a home automation system are typically adapted to operate according to one type of modulation. As a result, they cannot be used in another home automation system that implements another type of modulation.